Submission #4778445

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Source Code Expand

#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=a;i<b;i++)
#define rrep(i,a,b) for(int i=a;i>=b;i--)
#define fore(i,a) for(auto &i:a)
#define all(x) (x).begin(),(x).end()
//#pragma GCC optimize ("-O3")
using namespace std; void _main(); int main() { cin.tie(0); ios::sync_with_stdio(false); _main(); }
typedef long long ll; const int inf = INT_MAX / 2; const ll infl = 1LL << 60;
template<class T>bool chmax(T &a, const T &b) { if (a<b) { a = b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a = b; return 1; } return 0; }
//---------------------------------------------------------------------------------------------------
/*---------------------------------------------------------------------------------------------------
　　　　　　　　　　　 ∧＿∧  
　　　　　 ∧＿∧ 　（´<_｀ ）　 Welcome to My Coding Space!
　　　　 （ ´_ゝ`）　/　 ⌒i     
　　　　／　　　＼　 　  |　|     
　　　 /　　 /￣￣￣￣/　　|  
　 ＿_(__ﾆつ/　    ＿/ .| .|＿＿＿＿  
　 　　　＼/＿＿＿＿/　（u　⊃  
---------------------------------------------------------------------------------------------------*/









int N, Q; string S;
char T[201010], D[201010];
//---------------------------------------------------------------------------------------------------
int check(int x) {
	rep(i, 0, Q) {
		if (T[i] == S[x]) {
			if (D[i] == 'L') x--;
			else x++;
		}

		if (x < 0 or N <= x) return x;
	}
	return x;
}
//---------------------------------------------------------------------------------------------------
void _main() {
	cin >> N >> Q >> S;
	rep(q, 0, Q) cin >> T[q] >> D[q];

	int ans = N;

	if (check(0) < 0) {
		int ok = 0, ng = N;
		while (ok + 1 != ng) {
			int md = (ok + ng) / 2;
			if (check(md) < 0) ok = md;
			else ng = md;
		}
		ans -= ok + 1;
	}

	if (N <= check(N - 1)) {
		int ng = -1, ok = N - 1;
		while (ng + 1 != ok) {
			int md = (ok + ng) / 2;
			if (N <= check(md)) ok = md;
			else ng = md;
		}
		ans -= N - ok;
	}

	cout << ans << endl;
}

Submission Info

Judge Result